The present invention relates to a device for ATM (Asynchronous Transfer Mode) cell transfer in ATM communication system using AAL5 (ATM Adaptation Layer Type 5), an LSI (Large Scale Integrated circuit) unit, and a method for ATM cell transfer using AAL5.
Formerly, in a reassembly and segmentation processing of AAL5 (ATM Adaptation Layer Type 5), generally, priority is determined according to CLP-bit (Cell-loss priority bit) of ATM (Asynchronous Transfer Mode) cell header which CLP-bit is the priority in the ATM layer. The frame which is judged as the frame whose priority is low is discarded.
When the above described method is employed in such the reassembly and segmentation processing of the conventional device, in some cases, the priority of the upper layer is not reflected to the CLP-bit. Even though the frame which is a frame whose priority is high in the upper layer exists, such the frame with high priority is discarded caused by congestion in the ATM layer.
Further, when it causes the priority in the upper layer to be attempted to be reflected to the CLP-bit, it is not always reflected the priority accurately to the CLP-bit in the ATM cell header, because the CLP-bit is 1 (one) bit, while the priority in the upper layer is 4 to 8 bits.
In view of the foregoing, it is an object of the present invention, in order to overcome the above-mentioned problems, to provide reassembly and segmentation (SAR:segmentation and reassembly sublayer) function of AAL5 while causing the priority in the upper layer to be reflected in the reassembly and segmentation processing of the AAL5 in the ATM layer processing.
According to a first aspect of the present invention, in order to achieve the above mentioned object, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by the cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of the received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, and a selector for selecting the transmission frame sent from the storage means.
According to a second aspect of the present invention, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by the cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of the received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, a selector for selecting the transmission frame sent from said storage means, and a cell segmentation processing means for decomposing to be processed the frame selected from the selector into cell.
A third aspect of the present invention, in the first or second aspect, there is provided a device with quality controllable SAR function, wherein the identification addition means has a first priority part which discards low priority frame in order to perform congestion avoidance accompanied by prescribed quality due to reception of high priority frame while deciding processing condition from cell header information received and/or the information from upper layer within payload when the cell reassembly means is congested.
According to a fourth aspect of the present invention, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by the cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of the received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, and a selector for selecting the transmission frame sent from the storage means, wherein it causes a third priority part to be constituted by the storage means and the selector.
According to a fifth aspect of the present invention, in the second or forth aspect, there is provided a device with quality controllable SAR function according to upper layer instruction, wherein it causes a third priority part to be constituted by said storage means and said selector.
According to a sixth aspect of the present invention, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by said cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of the received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, a selector for selecting the transmission frame sent from the storage means, a frame processing part interface, and a host processor interface for performing communication to the host processor.
According to a seventh aspect of the present invention, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by the cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of said received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, a selector for selecting the transmission frame sent from the storage means, a cell segmentation processing means for segmenting to be processed the frame selected from the selector into cell, a frame processing part interface, and a host processor interface for performing communication to the host processor.
According to an eighth aspect of the present invention, in the third or fourth aspect, there is provided a device with quality controllable SAR function, which further comprises a frame processing part interface, and a host processor interface for performing communication to the host processor.
According to a ninth aspect of the present invention, in any of the first to eighth aspect, there is provided a device with quality controllable SAR function, wherein the first priority part and/or the second priority part and/or the third priority part decides priority while providing the order of priority more than 2.
According to a tenth aspect of the present invention, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by the cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of the received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, and a selector for selecting the transmission frame sent from the storage means, wherein the device with quality controllable SAR function is LSI device.
According to an eleventh aspect of the present invention, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by the cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of the received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, a selector for selecting the transmission frame sent from said storage means, and a cell segmentation processing means for decomposing to be processed the frame selected from the selector into cell, wherein the device with quality controllable SAR function is LSI device.
According to a twelfth aspect of the present invention, in any of the third to fifth aspect, there is provided a device with quality controllable SAR function, wherein the device with quality controllable SAR function is LSI device.
According to a thirteenth aspect of the present invention, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by said cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of the received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, a selector for selecting the transmission frame sent from the storage means, a frame processing part interface, and a host processor interface for performing communication to the host processor, wherein the device with quality controllable SAR function is LSI device.
According to a fourteenth aspect of the present invention, there is provided a device with quality controllable SAR function according to upper layer instruction, which comprises a frame storage means for executing reassembly of a frame of AAL5 (ATM Adaptation Layer Type 5) from an ATM (Asynchronous Transfer Mode) cell, an identification addition means for receiving a cell stream through a cell reassembly processor, and for adding an identifier on a basis of cell header information in order to introduce the cell which the frame storage means receives therein into the frame storage means or on the basis of upper layer information within a cell payload, a cell reassembly means for assembling the cell received by the cell reassembly processor, a next processing decision means having a second priority part for deciding either sending or abolition of the frame concerned on the basis of the received header on the occasion of sending the frame obtained from the cell received according to the cell reassembly processor and/or on the basis of the upper layer information within the payload, a storage means for storing therein an inputted transmission frame, a selector for selecting the transmission frame sent from the storage means, a cell segmentation processing means for decomposing to be processed the frame selected from the selector into cell, a frame processing part interface, and a host processor interface for performing communication to the host processor, wherein the device with quality controllable SAR function is LSI device.
According to a fifteenth aspect of the present invention, in the eighth or ninth aspect there is provided a device with quality controllable SAR function, wherein the device with quality controllable SAR function is LSI device.
According to a sixteenth aspect of the present invention, there is provided a quality control method for dissolving congestion while implementing reassembly of frame of AAL5 from ATM cell employing a device with quality controllable SAR function and employing an LSI device comprising the process of a first priority process for discarding low priority frame from among the frames on the basis of header information of the received cell and/or information within frame of payload, before determining reception of high priority frame, a second priority process for discarding frame of low priority from among the frames whose reassembly are completed in order to insure quality on the basis of cell header information of the frame whose reassembly is completed and/or on the basis of information within header of upper layer frame while supposing congestion of a frame storage means according to information quantity capable of being stored in said frame storage means, before determining reception of high priority frame, and a third priority process for deciding either loading or abolition of the frame for either transmission demand QUEUE or QUEUE transferring to a host processor according to informed processing result of the frame accompanied with the frame from the frame processing part.
According to a seventeenth aspect of the present invention, in the sixteenth aspect, there is provided a quality control method according to upper layer instruction, in said third priority process, said processing result of the frame is at least one information selected from among header information within device accompanying the cell, cell header information, and header information of the upper layer.